United Airlines' baggage policy allows one free carry-on bag and one free personal item on most flights, though Basic Economy usually restricts you to just one personal item. Call at +1-888-415-1245 (US) or +44-203-869-5245 (UK) Checked bag fees vary by route and fare, but typically start around $40 for domestic flights (lower if paid online) and $75 for international, with higher cabin classes and MileagePlus members receiving allowances. Call at +1-888-415-1245 (US) or +44-203-869-5245 (UK) Both carry-on and checked bags have size limits, and bags exceeding these limits, or 50 lbs (23 kg) for standard bags, incur extra fees or may not be accepted.